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Fetch the complete documentation index at: https://docs.localops.co/llms.txt

Use this file to discover all available pages before exploring further.

A complete walkthrough of instrumenting an Erlang service using prometheus.erl plus prometheus_httpd for the metrics endpoint. See the overview for the general approach.

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1. Add the dependencies

In rebar.config: 
{deps, [
    {prometheus, "4.11.0"},
    {prometheus_httpd, "2.1.11"}
]}.

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2. Register custom metrics and expose /metrics

prometheus_httpd:start/1 exposes /metrics and, with default collectors enabled, includes BEAM VM metrics (memory, schedulers, processes, atom table, ETS, ports). 
-module(metrics_app).
-export([start/0]).

start() ->
    ok = application:ensure_started(prometheus),
    ok = application:ensure_started(prometheus_httpd),

    prometheus_counter:declare([
        {name, emails_sent_total},
        {help, "Total number of emails sent"},
        {labels, [status]}
    ]),

    prometheus_httpd:start([{port, 9090}]),

    prometheus_counter:inc(emails_sent_total, [success]).
For Elixir applications, use PromEx instead — it bundles BEAM, Phoenix, Ecto, Oban, and Plug instrumentation with pre-built Grafana dashboards you can import as part of its setup.

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3. Declare the metrics endpoint in ops.json

{
    "metrics": {
        "endpoint": "/metrics",
        "interval": 15,
        "port": 9090
    }
}

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4. Visualize with a community dashboard

DashboardIDNotes
Erlang-Memory-Allocators18694BEAM memory allocator breakdown.
Erlang-Distribution17907Erlang distribution (inter-node) traffic metrics.
The canonical collection of BEAM dashboards is the prometheus-erl/beam-dashboards repository — it contains JSON dashboards covering memory, schedulers, processes, ETS, and more, that you can import directly into Grafana. To import: in Grafana, go to Dashboards → New → Import, enter the dashboard ID (or upload the JSON), and select your LocalOps Prometheus data source. You’ll see scheduler utilization, run queues, memory by allocator type, process counts, and ETS table stats. Your custom application metrics (emails_sent_total, etc.) can be charted alongside.